Andrew Bernstein is an elite age-group endurance athlete in Colorado whose pursuits have varied from road marathons to track cycling. He knows extreme fitness as an athlete and as an industry expert who studies e-bikes to vehicle equipment racks to wristwatches.
Throughout his career, Bernstein has overcome injuries, as well as a life-threatening accident in which he was hit on a training ride by a wayward driver who was sentenced to two years in prison.
Like many professional athletes, Bernstein uses data from a fitness tracker to monitor his vital signs, as well as more advanced physiology — from sleep patterns to power output during intense exercise.
More and more commonly, fitness trackers are being used by recreational walkers, hikers, runners, cyclists and swimmers to monitor their workouts and recovery. Sleep patterns, caloric intake, blood pressure, heart rate and mileage covered are all part of the ever-increasing physiological information available.
In 2020, about a decade after fitness wearables were first prominent, 20% of Americans used fitness trackers, according to The Pew Institute of Research. The global fitness wearable market value is growing even more quickly today; it was valued at $62.03 billion last year and $72.08 billion in 2025. It’s predicted to reach $290.8 billion by 2032, according to Fortune Business Insights, an online component of the global business publication.
Not all fitness wearables are the same. The information calculated is valuable, but product accuracy varies greatly. And not everyone agrees on the equipment’s importance. Detractors believe fitness enthusiasts who rely solely on the data from their devices can develop obsessive workout patterns.
“It can be overwhelming if you take that stuff super seriously, if you try to get it down to the 0.1 or even the 0.01,” says Aiden Urichko, manager of the Fleet Feet retail store in Fort Myers. “Some people are that strict about it. Obviously, a strict workout routine is not a bad thing. But once you get anxiety and stuff like that involved, then it becomes less healthy for you.”
Entry-level fitness watches may feature only a few functions including heart rate and distance. More expensive devices may include the ability to check blood oxygenation levels.
The Fitbit Inspire 3 ($89.95 to $99.95) includes basics: heart rate monitoring, workout tracking and sleep stage monitoring. The Apple Watch Series 10 ($429) features ECG and menstrual cycle monitoring, as well as irregular heart rhythm and sleep apnea detection. The Coros Vertix 2S ($699) features dual-frequency satellite tracking, 118 hours of full GPS use per charge and an optical heart rate sensor.
Regardless of the device, “The important thing is that it gives you a window into your physiology,” says Bernstein. “I think we can all agree that the best thing to do is something. All of the devices can measure something that you’re doing.
“For most people, the preciseness doesn’t really matter. What you want is to monitor trends. If you are seeing trends over time, it doesn’t really matter whether the rate was accurate to 1% or 5%. What’s important is that it’s accurate to itself.”
On the other hand, Andrew Weil, M.D., a pioneering integrative medicine physician, prolific author and renowned speaker, believes the devices are unnecessary and perhaps harmful.
“My main objection to the use of wearable devices for fitness or weight loss purposes is that they have the potential for generating anxiety,” Weil says. “It’s particularly so among people with eating disorders and those prone to exercising excessively.”
Even proponents of fitness wearables understand one of the devices’ potential problems: They espouse the products’ benefits, but only for recreational/informational use. The data does not diagnose, monitor, treat, prevent or cure any disease or condition.
The wearable health technology industry doesn’t have universal standards. Varying algorithms and sensor technologies are used by different brands. Inconsistent measurements between manufacturers are common. Wearable health data sharing by third parties is also not regulated, which may prompt users’ security and privacy concerns.
“The data is not an exact science,” says Bernstein. “But that’s a dilemma for some product testers to get hung up on. It’s not really a problem if you get a reading of 98 watts or 100 watts. It’s consistency over time that’s important.”
